Article Test

Alpha-particle emitting radioisotope Actinium225 (²²⁵Ac) is of great interest for use in Targeted Alpha Therapy (TAT) treatments of e.g., brain tumors, bladder cancer, neuroendocrine tumors and leukemia. A suitable ²²⁵ Ac radioligand is also potentially resolutive for the treatment of advanced and metastatic Castration-Resistant Prostate Cancers (mCRPCs). The mCRPC has a mean survival rate of 9-36 months and encompasses a heterogeneous ample range of molecular cancer behavior with a high risk of progression.

Global demand for the ²²⁵ Ac has spurred several production efforts including extraction from ²³³U, high energy protons or photon irradiation of ²²⁶Ra or spallation of ²³²Th by, at least, 100 MeV protons. Instead of using accelerators systems such as cyclotrons or LINACs, a Compact Neutron Generator (CNG) system has been developed. A 400kV-10 mA DC (D^_7Li) CNG potentially able to produce substantial amount of ²²⁵Ac with low ²²⁷Ac impurities is here presented. Exploiting the high flux of 10 and 13 MeV energy neutrons generated by the (D^_7Li) reactions to bombard a thin target layer of ²²⁶Ra, ²²⁵Ra/²²⁵Ac is produced via the ²²⁶Ra(n,2n)²²⁵Ra nuclear reaction. By irradiating a 5 mm thick ²²⁶Ra layer for 100 hours, about 11-13 mCi of ²²⁵Ac can be produced – corresponding to the TAT treatment of about 65 oncological patients – with an estimated ²²⁷Ac contamination of about one percent, which is below the acceptable limit for clinical use. This ²²⁵Ac production scheme by a suitable CNG should allow to adopt a local/regional approach avoiding the shipment costs of ²²⁵Ac.

The aim of this paper is to inform the production chain of radioisotopes to be used in medical field and the medical community involved in the application of radiopharmaceuticals for the cure of cancer, that a new technology based on Compact Neutron Generators (CNG) is in a R&D phase and will allow to produce the necessary quantity of radioisotopes for clinical and research purpose. This will be essential in treatment advanced metastatic cancer as for instance the metastatic Castration – Resistant Prostate Cancer.